The constitution of chaulmoogric acid : Pt. 1 / by Frederick B. Power and Frank H. Gornall.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1904.]
Catalogue details

Licence: In copyright

Credit: The constitution of chaulmoogric acid : Pt. 1 / by Frederick B. Power and Frank H. Gornall. Source: Wellcome Collection.

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    Ghaulmoogryl Alcohol, C18H33*OH. Fraction (1).—This fraction, which was not entirely soluble in warm aqueous potassium hydroxide, was therefore saponified with the latter, and the undissolved crystalline substance dissolved in ether. The ethereal solution was then extracted several times with concentrated aqueous potassium hydroxide, washed with water, dried, and the solvent removed. The residual, colourless oil soon formed a hard, crystalline cake, which, after recrystallisation, first from acetone and then repeatedly from methyl alcohol, separated in long needles, melting sharply at 36°. 0T016 gave 0-3016 C02 and 0-1162 H20. 0 = 81*0; H = 127. 0-1246 ,; 0-3688 C02 „ 0*1430 H20. C = 80*7 ; H = 12-8. C18H340 requires C = 81-2; H=12‘8 per cent. 5-48 grams in 100 c.c. of chloroform gave aD + 1°36' in a 50 mm. tube, whence [a]D +58*4°. Chaulmoogryl alcohol is unsaturated, for it readily decolorises a solution of bromine in chloroform. Fraction (2).—This was shown to consist entirely of chaulmoogric acid, no reduction to the dihydro-acid having taken place. Chaulmoogryl Chaulmoograte, C17H31*C02*C18H33. Fractions (3) and (4).—These were combined, dissolved in ether, the solution repeatedly extracted with aqueous potassium hydroxide, then with water, dried, and the solvent removed. The crystalline residue was recrystallised from ethyl acetate, from which it formed small, glistening rosettes, melting at 42°. 0-1430 gave 0-4272 C02 and 0-1572 H20. C = 81*5; H = 12-2. C36H6402 requires C = 818; H=12T per cent. This substance was definitely shown to be chaulmoogryl chaul¬ moograte by the fact that on hydrolysis it afforded on the one hand chaulmoogric acid and on the other chaulmoogryl alcohol, both of which were identified by their properties and by analysis. Reduction of Bromodihydrochaulmoogric Acid with Zinc Dust and Alcohol. Formation of Dikydrochaulmoogric Acid, c17h33-co2h. To a warm solution of 175 grams of bromodihydrochaulmoogric acid in alcohol, 60 grams of zinc dust were gradually added, and, after the introduction of the whole of the latter, the mixture was heated during